With the growing popularity of image forming apparatuses such as printers in the work and daily life, people become less content with using single-function image forming apparatuses. For example, the hybrid printers may provide multiple functions such as scanning, printing, and copying, etc., such that it is no longer necessary to place multiple separate apparatuses with different functions in the office space. Such arrangement saves the work space, reduces the business operation cost, and increases the employee work efficiency and quality.
Such a multi-function printer can be created based on a printer with only the printing function by adding a scanning device and a paper feed device that feeds paper to the scanning device to achieve the scanning function and the copying function, etc. The paper feed device is often located above the scanning device. Due to lack of paper handling structure such as paper cassette or paper guide in such paper feed device, paper sheets are likely to get into the paper feed path, causing damages to the front of paper sheets, and multiple paper sheets are likely to be fed into the printer together.
To solve the above described problems, a paper stop structure is often used in the conventional printers. FIG. 1 illustrates a schematic diagram of a conventional paper feed device of multi-function printers. As shown in FIG. 1, the paper feed device includes a paper feed structure 1, and a paper stop structure 2 configured at the paper entry of the paper feed structure.
When the printer is not in operation, paper sheets are blocked by the paper stop structure 2 from entering the paper feed path. When the printer is in operation, the paper stop structure 2 lifts up and the paper feed structure 1 draws paper sheets into the paper feed path. Specifically, the paper feed device also includes a connection rod 3 connecting the paper feed structure 1 and the paper strop structure 2. The connection rod 3 is swingably and pivotally mounted under an upper cover of the printer, and has a first connection member 5 and a second connection member 6. The first connection member 5 connects to the paper feed structure 1 and the second connection member 6 connects with the paper stop structure 2. The paper feed structure 1 and the paper stop structure 2 are connected by the connection rod 3 and move in opposite directions.
However, the paper stop structure 2 in the paper feed device only proves up and down, and the range of the movement is limited by the paper feed structure 1 and the upper cover. It is often impossible to feed a large number of paper sheets. As such, the paper feed capability of the paper feed device is limited, and the product applicability is also limited.